Method of making piano action flanges



Sept. 16, 1952 L. M. MARTIN 2,610,358

METHOD OF MAKING PIANO ACTION FLANGES Filed Dec. 16, 1949 2 smz'rs-smm 1 INVENTOR.

l/oya M/Yorf/n I Sept. 16, 1952 L. M. MARTIN 2,610,358

METHOD OF MAKING PIANO ACTION FLANGES Filed Dec. 16. 1949 2 SHEETS-SHEET 2 izlyff \\\\\\\\u:{D f2 5 2 2 i E E li IN V EN TOR. Z /0) d /7. Mar/Ir? Patented Sept. 16, 1952 UNITED PATENT OFFICE 1 a V v 2,610,353

' Memos or MAKING irmuo Ao'rioN FLANGES 1 I Lloyd -M.'Martin, San Francisco, .Calif., assignor to Winter'& Gompany, Inc., New -York,-N; Y., a

' corporation of New York Application mania. 1s, 1 9 i9, S erial' No. 133, 148

4 O1aims. (01'. 18447.5)

This invention relates to the manufacture of what are referred to in the piano art as flanges, by which is meant the brackets which are secured to the action flange rail and which serve as pivot supports for the hammers and other movable components of a piano'action. A multi plicity of such flanges is required for each piano and the object of the invention is to facilitate and reduce their cost of manufacture by plastic molding in such fashion that the resulting flanges are complete, even to the inclusion of the'n'ecessary bearing material in the journal portions of the flanges. ,1 f

The invention will be'readily understood from the following description taken in conjunction with the accompanying drawings, in which:

Fig. 1 is a broken-out vertical elevation, partially sectioned, of a part of a piano action showing a flange incorporated therein;

Fig. 2 is an enlarged scale sectional View of a flange, the section being taken on the line 11-11 of Fig. 3;

Figs. 3 and 4 are, respectively, front and rear elevations of the flange of Fig. 2;

Fig. 5 illustrates a preferred form of wrapped core wire suitable in the practice of the method of the invention;

Fig. 6 is a face view of a mold half for molding flanges in accordance with the invention and with the wrapped core wire positioned in the mold; and

Fig. 7 is a view of the complete molded unit as it appears when removed from the mold.

Referring to Fig. 1, a flange l is shown attached to action flange rail 2 by screw 3, the flange providing the pivot support for the butt 4 of hammer 5. Such arrangement is of standard, Well-known construction.

As shown more particular y in Figs. 2, 3 and 4, the flange consists of a body portion 6, recessed on the back (as at 1) to fit the flange rail, and having a hole 8 to receive the screw 3 by which the flange is secured to the rail. from the body portion of the flange are spaced arms 9 which have aligned openings 9a which are lined or bushed with suitable bearing material 10 for the pivot pin ll of (in this instance) the hammer butt, as shown in Fig. 1.

According to the present invention, such flanges are plastic molded, singly or in groups, with a core sheathed in suitable bearing material so placed in a mold as to form the openings 9a in the flange arms. After removal from the mold, the core is withdrawn, leaving the flange or flanges on or united by the bearing material and Upstanding the" surplus bearingmaterial" protruding from the -m'olded parts isthen severed, leaving the pivot holes'bushed and ready. for use. The bearing material customarily used and suitable for the present method, is felt.

- The core referred to preferably consists 'of a stiff wire [2 (Fig. 5) of the same'diameter'as the pivot pins with which'theiflanges are ultimately'to be 'us'ed; and this coreis suitably encased in a sheath of :bearing material... 'When 'felt is 'used,'-it is preferably applied in'strip'form and wrapped'helicall-y around the core wire, as indicated at 13 in Fig. 5. Theends of the'felt may be temporarily secured to the coretwire by clips (not illustrated) or by any other suitable means. At this juncture, if desired, the surface of the felt sheath can be sealed, as by the application of a thin coating of glue.

The core-supported felt or bearing material is then placed in one of the mold halves I4 as illustrated in Fig. 6, the felt being so positioned with respect t cavities I5 as to bridge the cavity portions 16 which, as will be understood, are to form the spaced flange arms 9. The arrangement of the several cavities is schematic only, as will be understood, although for obvious reasons of economy and speed of production it is preferable to mold an extended series of closely spaced flanges at one time. After molding, the complete unit removed from the mold appears as in Fig. 7.

At this stage, the inner or bearing surface of the felt or sheath may be ironed; and this may be effected by holding the flanges in a suitable fixture and rotating the core wire. By this means sufficient heat can be generated to effect the ironing. As will be understood, the molding of the flanges directly onto the bearing material effects a bond between the bearing material and the walls of openings 9a in the flange arms, and the core wire can be withdrawn, leaving the series of flanges united simply by the tube of bearing material.

To separate and complete the flanges, it is merely necessary (after removing the core wire; to sever the protruding portions of felt by cutting along the dotted lines shown in Fig. '7, that is to say, along the inner and outer faces of the flange arms 9. As will be recognized, this operation can likewise be performed quickly and economically by means of a series of cutters applied simultaneously to the fixture-held group of flanges. Thus separated and with the openings in their arms 9 lined with the remaining felt use.

It will be understood that the plastic materials suitable for making the flanges are the conventional, injection moldable, organic plastics of which a number available.

- In the light of the foregoingthe following is claimed:

of varieties are commercially 1. The method of making piano action flanges which comprises: wrapping a strip of bearing,

.and the flanges molded thereon but leaving said felt wrapping attached to said flanges; and severing thefelt Wrapping protruding from each of the flanges.

2. The method of making piano action flanges which comprises: enclosing a core wire with a sheath of bearing felt; simultaneously molding aseriesof closelyspaced plastic flanges about the felt-enclosed. wire and attaching said felt to the flanges as thelatter are formed; with 3 drawing the core wire from the felt and the flanges molded-thereon while maintaining the felt attached to the flanges; and severing the felt sheath portions protruding from the flanges.

3. The method of making piano action flanges which comprises: enclosing a core wire with'a sheath of bearing material; molding a plastic flange about the sheathed core wire and coincidently attaching the bearing material to the flange; removing the core wire while maintaining the bearing material attached to the flange; and severing the bearing ,material protruding from the flange.

4. The method of making bushed plastic piano action flanges which comprises simultaneously molding in one molding operation a group of spaced plastic flanges directly about an elongated core-supported tube of bearing material, bonding the tube of bearing material to the flanges as the latter are formed, removing the core from the tube ofbearing material without breaking the bond between said tube and the flanges, and then cutting the bearing material extending from each flange, leaving the bonded bearing material in the flange to serve as bushing.

LLOYD M. MARTIN. 7

REFERENCES Ci'rn'n The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 473,242 Shailer Apr. 19, 1892 1,650,095 Rydberg Nov. 22, 1927 2,074,368 Corner Mar. 23, 1937 2,130,177 Doak Sept. 13, 1938 2,389,952 Brown Nov. 27, 1945 

